Creating circuit designs targeted to programmable integrated circuits can be challenging because of aggressive timing requirements imposed by applications. A designer may use certain software tools early in the design process, such as before a design has been mapped, placed, or placed and routed, to identify and remedy potential timing problems. Timing problems may be easier to fix if identified early rather than late in the design implementation flow. If timing issues persist after a design has been mapped, placed, or placed and routed, changing the design to achieve timing goals becomes much more difficult.